There\u2019s a problem, however: these living pest-removers are sensitive to travel stress, and many die while being transported by truck or boat from the lumpfish farms where they\u2019re born to the salmon farms where they\u2019ll be put to work. Now, a team of Norwegian researchers has evaluated<\/a> a variety of anesthetics, testing each to see how effective it is at knocking lumpfish out. By unraveling the best way to put them under, the scientists hope to keep more lumpfish alive en route.<\/p>\n In Norway, the Atlantic salmon aquaculture industry has an annual haul of 1.1 million tonnes valued at more than US $7-billion. But fish faming in Norway and elsewhere is undermined by salmon lice<\/a>. These parasitic crustaceans feed on the skin, blood, and tissues of finfish. In aquaculture sea pens, where their preferred hosts are housed by the thousands, salmon lice run rampant.<\/p>\n As they eat their way through the protective mucus layer on their host\u2019s skin, lice leave the salmon vulnerable to disease. With enough skin damage, the situation becomes more acutely lethal. \u201cThe fish aren\u2019t able to osmoregulate,\u201d says Kjell Maroni, the director of research and development for aquaculture at the Norwegian Seafood Research Fund, who worked on the new study. A heavily infected salmon will start to lose water to the mineral-rich ocean around it, upsetting its internal water-salt balance. Essentially, it gets pickled by its salty home.<\/p>\n Lice infestations are a global problem. In North America, salmon lice are among the biggest limiting factors to an increase in salmon aquaculture. \u201cSome sites are so bad that farmers have to leave the sites fallow for a few years,\u201d says Brian Peterson, an aquaculture specialist at the US Department of Agriculture\u2019s National Cold Water Marine Aquaculture Center in Maine, who was not involved in the study.<\/p>\n Traditional methods to control lice include bathing the fish in hydrogen peroxide, feeding them food with additives aimed at preventing lice from attaching, pressure washing the lice away, and using powerful pesticides. Tamer treatments show varying levels of success, while the harshest options can stunt the salmon\u2019s appetite and growth. What\u2019s more, most of the treatments are losing effectiveness.<\/p>\n \u201cNo one likes to use chemicals to control sea lice,\u201d says Peterson. \u201cSea lice build up resistance and the process of treating the fish is very stressful. Lumpfish provide an alternative to chemicals and it is a welcome relief,\u201d he says.<\/p>\n In Norway, the increasing use of lumpfish to control salmon lice has propelled production of the tiny parasite-eater, and similar cleaner fish programs are taking off elsewhere<\/a>.<\/p>\n The lumpfish are transported as juveniles, so care needs to be taken to find an anesthetic that is not too strong. Photo by Paulo Oliveira\/Alamy Stock Photo<\/p><\/div>\n![\"Lumpsucker](\"https:\/\/hakaimagazine.com\/wp-content\/uploads\/pen-lumpfish-aquaculture-1200x750.jpg\")
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